Water-motor for rock-drills.



, 'ervaren serres earner `ervaren A GEORG EMIL GJUKE, OF STOCKHOLM, SWEDEN.

WATER-MOTOR FOR ROCK-DRILLS.

To all whom t may concern: y

Be it known that I, GEORG EMIL GJUKE, a subject of the King of Sweden, and resident of 26 St. Eiilrsgatan, Stockholm, Sweden, have invented certain new and luseful Improvements in 1i/Vater-lvotors for ,Rock- Drills, of which the following is a specification.

The present invention refers to a hydraulic machine with slide motion, especially intended for rock-drilling, vand is I characterized by the connection of the slidechamber with the cylinder-chamber in such a manner, that on reversing the slide no sudden change of the pressure in the cylinder occurs, and the pressure in the cylinder'l can never rise alcove the maximum pressure in the tubes. One form of construction of the invention yis arranged'in such a manner, that the slide at one and the same time never shuts oli"1 the connection between the inlet and outlet chambers respectively of the cylinder-chamber and the slide-chamber, but in its middle position always leaves a narrow opening to both. According to another form of construction the cylinder-chamber, or a chamber connected with the same, is arranged in such a manner that its volume is changed on reversing the slide, so that a sudden vchange in the pressure is prevented.

The invention is illustrated in the accom-V panying drawing, in which Figures 1 and 2 show in vertical section the aforementioned two forms of construction. Fig. 3 is a fragmentary view of the slide-valve, and` the port controlled thereby.

n the form of construction shown in Fig. 1, the cylinder 2 is connected with a slidechamber 6, through passages'3, 4 and 5. The passage 4 connects with the cylinder through a port 23, and the passage 5 through the ports 21, In chamber 6 is arranged a slide 7, shaped in such a way that the slide-chamber is divided into three compartments, of which chamber 8, which is'provided with an inlet. not shown in the drawing through channel 3, the chamber 9 through the channel 4 and the chamber 10 through channel 5 are connected with the cylinder-chamber. The slide is provided with a channel 11 and openings 12,- which place the outlet 13 `for the water Vinto connection with the slidechamber 9. At one end of lthe slide-chamber there is another chamber 14, connectedY with the chamber v15 behind the piston 1. This latter is at one point provided with a Specification of Letters Patent.

`Patented Apr. 16, 1918.

Application fuealnarch is, 1914. serieu No. 825,709.

reduced portion 1G, forming a circular chamber 17 between Acylinder `and piston. Finally the cylinder is ,at one point through an opening 18 connected with the .channel 3. According ,to ythe invention, part 19 of the slide 7 .is slightly smaller than the inlet 20 into chamber 15 behind piston l, so that it does not entirely shut ofi' the connection between this chamber land the cylinder, which would result in a violent shock on reversing the movement. v

The device operates in the following manner. The kchannel 3 is constantly connected with the inlet for the water, .and there vis therefore always pressure in the same. The

water acts now through the opening 2.0 and the chamber 10 and act upon the back of the slide, retaining the latter in the position shown in the drawing. When the edge 22 of the piston has passed the port 23, the chamber 10 is connected with the `chamber 9 through the channels 4 and 5, and this.

chamber 9 is by means of the openings 12 and channel 11 in the slide connected with the outlet '13. lWater coming into channel 3 and then into chamber 8 is under normal pressure. rThe unbalanced pressures on the valve eiect thevmovement of ythe VSlide to the right, wherebyV the inlet 20 to the back of the piston is irst throttled and then connectediwith the outlet 13. 1t is lof course understood that the diameter of the valve 7 is slightly greater than v,that of the valve 19. Since the force required to move vthe slide is only smal-l, a slight difference in the respective diameters of the valves 7 and 19 is sufcient to provide a balance to push the slide to the right. By ythis means the pressure is removed from the rear face of the piston which may be thrown backby the water in the channel 3. When part- 19 of the slide reaches a position right opposite and this has the result, as has been menj tion'ed previously, that no shock can occur on reversing. d

When the piston, after the drill has struck the rock or otherwise has reached its eX- treme position, has turned and is on its return trip, and has traveled far enough for the reduced portion 16 to connect the channel 3 through the port 18, the ports 21 and the channel 5 with the chamber 10, the slide is brought back to the position shown in the drawing, whereby the outlet from the chamber 15 is shut oft', and this latter is instead 1n the form of construction shown in Fig.

2 the slide 24 is arranged in the rear part of the cylinder. 25 is theV inlet and 26 the outlet for the water. 27 are inclosed channels through which the chamber 28 in front of the piston can be connected with the chamber 29 behind the same. Through the channel 30 the water is constantly connected with the chamber 36 behind the slide. 31 are inclosed channels which through openings 32 and 33 are connected with the cylinder-chamber. In the position in which the parts are shown in the drawing the piston has on its forward trip just passed the opening 34, and in so doing shut off the chamber 29 behind the piston from its connection through channel 27 with the water, while the latter in the chamber 36 still continues to act upon the back of the slide and propels the same forward in the same direction as the piston, which results in the cylinder-volume being altered, while the pressure is only reduced slowly. When the slide has uncovered the openings 33, the chamber 29 between the slide and the piston is through the openings 32, vthe channels 31 and the openings 33 connected with the outlet 26, so that the pressure is removed from the rear face of the piston. The slide 24 abuts against the shoulder of the chamber 29 thus preventing the fluid pressure on the rear end of the slide from being transmitted to the piston. The water entering chamber 28 in front of the cylinder reacts on the shoulder of the piston thereby reversing its direction of travel. As soon as the piston has covered the openings 32, the chamber 29 is shut ofi' from the outlet, whereby on the pistons continued backward motion, on account of its momentum, there occurs an increase in the pressure in chamber 29, so that the slide is brought backward, being assisted by the water which has in the meantime entered through the uncovered passages 34 and 35. Wien the openings 35 into the channels 27 have been runcovered by the slide, fresh water pours into the chamber behind the piston, pushing the latter forward and retaining the slide in its back position. On the slide moving backward, there occurs a distinct increase in the cylinder-volume, by which the violent increase of presure, which would otherwise occur on shutting oif the chamber 29 from the outlet, is eliminated and the increase of pressure eected slowly and is prevented from eX- ceedingthe pressure in the pipes.

Having now particularly described and ascertained the nature of my said invention and in what manner the same is to be performed 1 declare that what l claim is.

1. In a hydraulic machine, a cylinder, a piston therein, a slide chamber, aV slide therein, fluid passages connecting said cylinder and said slide chamber, said fluid passages controlling the movement of said piston and said slide and means for. preventing a ram-action as the piston reaches the end of its stroke, said means comprising provisions to reduce the pressure of the driving Huid at one end of a stroke and to maintain a counter pressure at the other end of a stroke.

2. In a hydraulic machine, a cylinder, a slide-chamber provided with three compartments, a passage between each of said compartments and said cylinder, one of said compartments being in continuous communication with the fluid-supply, another of said compartments being in continuous communication with the exhaust, a port connecting one end of said cylinder with the fluid-supply, a slide in said slide-chamber, a

disk-valve on said slide and controlling said port, said disk-valve being of less thickness than the width of said port, and a piston in said cylinder having a reduced portion Vconnecting during the movement ofthe piston the passage of the third compartment alternately with the passages of the other compartments. y

3. In a hydraulic machine, a cylinder, a piston therein, a slide chamber, av slide therein, fluid passages connectingY said cylinder and said slide chamber, said fluid passages controlling the movement of said piston and said slide, and means for preventing a ram-action as the piston reaches the end of its stroke, said means comprising provisions to gradually reduce the pressure of the driving iuid at one end of the stroke and to maintain a counter-pressure at the other end of the stroke.

4. 1n a hydraulic machine, a cylinder, a piston therein, a slide chamber, a slide therein, uid passages connecting said cylinder and said slide chamber, said fluid passages controlling the movement of said pist0n and said slide, and means for preventing a ram-action as the piston reaches the end of its stroke, said means comprising name to this speoioation in the presence of prol/lisins to gadually releae thehpressule two subscribing Witnesses. of t e rivin uid at one en of t e stro e Y and to maingtain a substantially uniform GEORG EMIL GJUKE 5 counter-pressure at the other end of the Witnesses:

stroke., ITFRG C. CRUTHS,

In testimony whereof I have signed my T. JoNsoN.

Copies of this patent may be obtained for ive cents each, by addressing the Commissioner of Patents,

Washington, D. C. 

